Single-Molecule Electron Transport on C60–PtSe2 Organic–2D Transition Metal Dichalcogenide Heterointerface

Abstract Charge transport across organic–inorganic heterointerfaces plays a pivotal role in molecular electronics, yet remains insufficiently understood at the molecular scale. Here, we investigate single-molecule Au–C60–PtSe2 junctions using the STM break-junction technique under ambient conditions, complemented by DFT-NEGF calculations. Compared with symmetric Au–C60–Au junctions, the Au–C60–PtSe2 junction exhibits a lower conductance by approximately two orders of magnitude (∼120×) and a current rectification ratio of 5.2. Current–voltage measurements reveal asymmetric charge transport, which is well described by a single-level transport model. The extracted parameters indicate extremely weak electronic coupling at the C60–PtSe2 interface relative to the Au–C60 contact. Theoretical calculations identify the C60–PtSe2 contact as the dominant transport bottleneck despite the semimetallic character of the PtSe2 electrode. These results quantitatively resolve charge transport across an individual organic–transition metal dichalcogenide (TMD) contact and highlight the key role of interfacial coupling in governing molecular transport at conducting layered electrodes.